What is the standard for determining whether a conviction must be set aside because of federal constitutional error?

In Chapman v. California ... we held that the standard for determining whether a conviction must be set aside because of federal constitutional error is whether the error "was harmless beyond a reasonable doubt." In this case we must decide whether the Chapman harmless-error standard applies in determining whether ... [prosecutorial misconduct] entitles petitioner to habeas corpus relief. We hold that it does not. Instead, the standard for determining whether habeas relief must be granted is whether the ... error "had substantial and injurious effect or influence in determining the jury's verdict."